After April 8, 2014, Microsoft will no
longer provide security updates or technical support for
Windows XP. Security updates patch vulnerabilities that may
be exploited by malware and help keep Users and their data
safer. PCs running Windows XP after April 8, 2014, should
not be considered to be protected
Quelle:
https://www.microsoft.com/en-us/WindowsForBusiness/end-of-xp-support